Japanese popular singer and actress Maiko Kuraki was invited to attend the new product launch of a diamond brand. Wearing a black long-tailed dress and a necklace studded with more than 2000 diamonds, Maiko Kuraki showed a bit of noble coquetry like a black swan. It is reported that the diamond necklace Maiko wore weighed about 40 carats and cost as high as 50 million yen.